I purchased a bearing splitter, similar to what Voltaire showed above, in order to ease a couple of the bearings off, where they are too tight against gears to allow the puller to gain purchase. I figure better to buy a tool as you need it - & save damage bodging. That way I have it for next time

The garage door guys came & installed a new garage door & opener for my workshop. Goodbye to the rusted heavy manual door.

The gearbox drain has been repaired with a bronze insert, staked inside the case. Nice.

The output shaft with circlip. Exciting, I know. Well maybe to just to me...

Here's a video as to why that circlip is important

Regarding the carb mod, there is a write up over in the ‘water crossing thread’. This is to increase the wading depth of Gus in stream crossings.

John also repaired one of the choke stops with a stainless pin. The prior cast one had broken off when I was trying to get the choke lever nut to undo.

I got five of the gearbox bearings from Mana Bearings, but they cannot economically provide the input bearing. If I import this, I may as well have got all of the bearings as a kit from offshore. Doh! At least the five bearings I already hold are a known quantity. I’ve already ordered new seals & ancillaries from Motobins.

Today: [LIST] The output shaft with circlip. Exciting, I know. Well maybe to just to me.... .

And to me. Had it done twice. First as a preventative measure to my 1989 R100RS while Mike was in there to deal with a failed gear change return spring. Second when getting the R80GS gearbox rebuilt after taking it off the road 10 km or so before it finally let go due to the lack of the circlip!

I had a suspicion the R80GS had ingested water during two deep and prolonged wades on the 2013 Safari early this year, but was too lazy to check. Both final drive and gearbox were filled with pink mayonnaise (formerly red synthetic 75/90) when I did my annual service a few weeks ago. Couple of thousand km run on this!
However, I am not going to lose any sleep over this.
Regards,
Michael

so you gonna run the carb and drive breather up under the tank?Is that where you already have the gearbox breather....do you still run the std airbox and snorkel,that will be the next impediment?

Yes.

Quote:

Originally Posted by msmckeon

I had a suspicion the R80GS had ingested water during two deep and prolonged wades on the 2013 Safari early this year, but was too lazy to check. Both final drive and gearbox were filled with pink mayonnaise (formerly red synthetic 75/90) when I did my annual service a few weeks ago. Couple of thousand km run on this!

Daylight savings is all very well, but trying to kick start two reluctant heroines into getting ready within a reasonable time was the challenge of the day. One had been out partying; the other just doesn’t do mornings. I’ll allow you to guess which one is which.

The ride was due to start at J’ville Community Centre. Given we were the closest to the destination, obviously we were going to be the last to arrive. There was a small delay for deferred bike maintenance, then a magical mystery tour of J’ville backroads.

The Ohariu Farm is a conference venue, which only opens once a month for Brunch. Very nice I must say. I now recall that we had a function there about 5 years ago. Here's the brunch menu

After brunch we took a tour to Makara, had a chat on the beach, and then rode to Karori. I took a couple of photos part way up the big hill, & along toddled Michael Dodson on his Bopper, on his way to the ‘Distinguished Gentlemens’ ride.

Sorry I didn’t end up taking photos guys. That was why I originally stopped on the Karori Hill, but I got distracted. I got one blurry short of Mandy, & an okay shot of Michael.

For what was supposed to be a rainy day, it was a surprising nice (sunny) day.

The continuing gearbox rebuild is on the agenda for this arvo. I find I do not have the enthusiasm for work today.

I took a couple of photos part way up the big hill, & along toddled Michael Dodson on his Bopper, on his way to the ‘Distinguished Gentlemens’ ride.

Which is where I went today, on my anodyne and out of place GS. Should have taken the RD. It would have fit right in but is unwarranted and unregistered (which would probably also have helped it fit in even more).
Very relaxed ride, 2 hours to make our way from Oriental Bay to the Southern Cross, via the south coast.
Michael

I didn’t disassemble the input shaft – I didn’t have anyway of relieving the spring pressure on the circlip. Maybe next time. As a result, I haven’t replaced the input shaft roller bearing & bush. The bush has some marks from the prior seal. The bearing has quite a bit less movement than the corresponding bearing that came out of the RS. Next time maybe.

The little input shaft pushrod seal is a truly trying little piece of German engineering. I needed to pull the input shaft output side bush off the shaft to allow me to punch this through & out of the back of the bush. Then I reassembled the seal into the bush from the rear, pushed it through to the front, & then pressed the bush back onto the shaft. The corresponding bearing got a nice new baffle on the input side, given I’d munted that getting the old bearing off.

The layshaft bearings were replaced. I used the bearing splitter on one as there was not clearance between the bearing & the nearest gear.

As much as I would have liked a lower 1st, I was too cheap to buy this & the shaft would have required a big press to remove & replace this. Likewise the higher fifth (though this was less attractive for me).

I heated the bearings in hot oil, & froze the shafts. I still needed to ‘persuade’ the bearings to go on.

I put a spring clip under the circlip, to allow for the radius in the input side output shaft bearing. Nice & tight. Hopefully won't move.

Parts diagram courtesy of Max BMW. I had to reassemble the output shaft twice. I put a washer in the wrong place, noted some slop on the middle gear (11 above). I realized my mistake, & had to pull the output side bearing again to correct this.

I haven't replaced the selector forks, or the bronze bush (14 above) that was showing some marking.

To reassemble the gearbox, the layshaft, output shaft, & one gear selector needed to be repositioned in the gearbox as one assembly. The other 2 selector forks could be installed after the event because the shaft they moved on was able to be removed. I had to push the layshaft & output shaft into the gearbox three times. The first time the shaft slid in fairly nicely, but I realized too late that I hadn’t put in the one selector on the immoveable shaft. Consequently I had to reheat the gearbox case end in order to release the gear shafts again. The second time the gearbox wasn’t hot enough (I was rushing), & the bearing hung up in the case. The third time I heated the box longer & hotter (150 degrees in Mandy’s oven – but the case was spotless your honor). Perfect. I'll add more photos tomorrow. And I'll start to look at the shimming.

Don't need that gearbox to do the CtC. Doing the shimming. Vernier calipers aren't really accurate enough to help with that. Doing lots of sampling to get a more accurate 'fix'.

End float just didn't seem right, given the shims that had been in the box, so heated the gearbox end again & gave the shafts another wack. This time they settled in properly.

Did a little spreadsheet to calculate the shims needed, copied off Joergs.. I don't think he included the gasket, & he must have included the layshaft baffle in the shims.

Nearly forgot to put in the pressed steel oil trap.

The output seal was a pain to get out, & later a pain to get back in.

Heated the cover in the oven at 150 degrees again (the oven was already hot - we had pizza tonight). This time I got an earful because the cover must still have had some oil on it, so it was rather more fragrant in the kitchen than Mandy was prepared to tolerate.

Do you put on extra gasket cement or put on the gearbox gasket dry? I assumed dry. By that I decided that laying a bead of sealant on a hot gearbox cover wasn't for me.

Put a bit of grease on the shims & baffles to hold them in. Then retrieved the cover from the kitchen, eased it on, gave it a few wacks to settle it over the bearings, then tightened the allen bolts. So what torque setting for the cover bolts. Clymer gives 9ft lbs for 4 speeds & 24 ft lbs for 5 speeds. The 24ft lbs is plain wrong. The BMW manual says 10nm, which is 7.4 ft lbs or thereabouts. So I feel comfortable with the 9ft lbs.

Good stuff Nutso. I left mine up to the mechanic to refit so i don't know what he did.

Oh yeah you know that high pitched whining my bike was making? I worked out a hundred metres from returning home last nite that it is only in 4th gear

I will make sure next ride.

Motul Gearbox 80W - 90. Its got moly(insert big word here)shit in it and it made my gearbox sound better and change more smoothly.
In a nutshell, it did what it said it would do
Bugger me hope that doesnt catch on